Forceps

ABSTRACT

A forceps includes first and second shaft members, each having a jaw member disposed at a distal end thereof. The first and second shaft members are pivotably coupled to one another toward the distal ends thereof and are moveable relative to one another between an open position and a closed position for moving the jaw members between a spaced-apart position and an approximated position. A knife assembly including a handle and a knife extending from the handle is also provided. The knife assembly is selectively translatable between a retracted position and an extended position, wherein the knife extends between the jaw members. The handle is disposed between the first and second shaft members and is configured to block further closure of the first and second shaft members beyond the closed position, thereby defining a minimum gap distance between the jaw members.

CROSS-REFERENCE TO RELATED APPLICATIONS

This present application is a continuation application of U.S. patentapplication Ser. No. 13/166,497, filed on Jun. 22, 2011, the entirecontents of which are hereby incorporated by reference herein.

BACKGROUND

The present disclosure relates to a forceps and, more particularly, to asurgical forceps for sealing and/or dividing tissue.

TECHNICAL FIELD

A forceps is a plier-like instrument which relies on mechanical actionbetween its jaws to grasp, clamp and constrict vessels or tissue.Electrosurgical forceps utilize both mechanical clamping action andelectrical energy to affect hemostasis by heating tissue and bloodvessels to coagulate and/or cauterize tissue. Certain surgicalprocedures require more than simply cauterizing tissue and rely on theunique combination of clamping pressure, precise electrosurgical energycontrol and gap distance (i.e., distance between opposing jaw memberswhen closed about tissue) to “seal” tissue, vessels and certain vascularbundles.

Typically, once a vessel is sealed, the surgeon has to accurately severthe vessel along the newly formed tissue seal. Accordingly, many vesselsealing instruments have been designed which incorporate a knife orblade member which effectively severs the tissue after forming a tissueseal.

SUMMARY

In accordance with one embodiment of the present disclosure, a forcepsis provided. The forceps includes first and second shaft members and aknife assembly. Each of the first and second shaft members includes ajaw member disposed at a distal end thereof. The first and second shaftmembers are pivotably coupled to one another toward the distal endsthereof. One (or both) of the first and second shaft members is moveablerelative to the other between an open position and a closed position formoving the jaw members between a spaced-apart position and anapproximated position. The knife assembly includes a handle and a knifeextending from the handle. The knife assembly is selectivelytranslatable, relative to the shaft members, between a retractedposition and an extended position. In the extended position, the knifeextends between the jaw members. The handle is disposed between thefirst and second shaft members and is configured to block furtherclosure of the first and second shaft members beyond the closedposition, thereby defining a minimum gap distance between the jawmembers.

In one embodiment, the minimum gap distance between the jaw members isin the range of about 0.001 inches to about 0.006 inches.

In another embodiment, each shaft member and its respective jaw memberis monolithically formed as a single component.

In another embodiment, one or both of the jaw members is adapted toconnect to a source of electrosurgical energy.

In still another embodiment, the handle of the knife assembly defines afinger ring configured to facilitate translation of the knife assemblybetween the retracted position and the extended position.

In yet another embodiment, one or both of the jaw members includes alongitudinally-extending knife channel defined therein. Thelongitudinally-extending knife channel is configured to permitreciprocation of the knife therethrough.

In still yet another embodiment, the knife includes a longitudinal slotdefined therein. The longitudinal slot of the knife is configured toreceive a pivot pin therethrough upon which the first and second shaftmembers are pivotably coupled. The pivot pin is configured to translatelongitudinally along the slot as the knife assembly is translatedbetween the retracted position and the extended position.

Another embodiment of a forceps provided in accordance with the presentdisclosure includes first and second shaft members and a knife assembly.Each of the first and second shaft members includes a jaw memberdisposed at a distal end thereof. The first and second shaft members arepivotably coupled to one another toward the distal ends thereof and oneor both of the shaft members is moveable relative to the other betweenan open position and a closed position for moving the jaw membersbetween a spaced-apart position and an approximated position. The knifeassembly includes a handle and a knife extending from the handle. Theknife assembly is selectively translatable between a retracted positionand an extended position. In the extended position, the knife extendsbetween the jaw members. The handle is disposed between the first andsecond shaft members. More specifically, a portion of the (or theentire) handle is disposed within a guide track defined within one orboth of the shaft members. The guide track is configured to guidetranslation of the knife assembly between the retracted position and theextended position.

In one embodiment, one or both of the shaft members includes alongitudinal trough defined therein. The longitudinal trough forms theguide track for guiding translation of the knife assembly between theretracted position and the extended position.

In another embodiment, the handle of the knife assembly and the guidetrack define complementary transverse, cross-sectional configurations tofacilitate translation of the knife assembly between the retractedposition and the extended position.

In another embodiment, the handle of the knife assembly defines a fingerring configured to facilitate translation of the knife assembly betweenthe retracted position and the extended position.

In still another embodiment, each shaft member and its respective jawmember are monolithically formed as a single component.

In yet another embodiment, one or both of the jaw members is adapted toconnect to a source of electrosurgical energy.

In still yet another embodiment, one or both of the jaw members includesa longitudinally-extending knife channel defined therein. Thelongitudinally-extending knife channel is configured to permitreciprocation of the knife therethrough.

A forceps in accordance with another embodiment of the presentdisclosure is provided including first and second shaft members and aknife assembly. Each shaft member has a jaw member disposed at a distalend thereof. The shaft members are pivotably coupled to one anothertoward the distal ends thereof and one or both of the shaft members ismoveable relative to the other between an open position and a closedposition for moving the jaw members between a spaced-apart position andan approximated position. The knife assembly includes a handle and aknife extending from the handle. The knife assembly is selectivelytranslatable between a retracted position and an extended position. Inthe extended position, the knife extends between the jaw members. One orboth of the shaft members includes a guide track for guiding translationof the knife assembly between the retracted and extended positions. Thehandle of the knife assembly is disposed between the first and secondshaft members and is configured to define a minimum gap distance betweenthe jaw members when the jaw members are disposed in the approximatedposition.

In one embodiment, one or both of the jaw members is adapted to connectto a source of electrosurgical energy.

In another embodiment, the minimum gap distance between the jaw membersis in the range of about 0.001 inches to about 0.006 inches.

In another embodiment, one or both of the jaw members includes alongitudinally-extending knife channel defined therein. Thelongitudinally-extending knife channel is configured to permitreciprocation of the knife therethrough.

In still another embodiment, the handle of the knife assembly and theguide track define complementary transverse, cross-sectionalconfigurations to facilitate translation of the knife assembly betweenthe retracted position and the extended position.

In yet another embodiment, the handle of the knife assembly defines afinger ring configured to facilitate translation of the knife assemblybetween the retracted position and the extended position.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the present disclosure are described herein withreference to the drawings wherein:

FIG. 1 is a side view of a forceps according to one embodiment of thepresent disclosure wherein jaw members of the forceps are disposed in aspaced-apart position;

FIG. 2 is a side view of the forceps of FIG. 1 wherein the jaw membersare disposed in an approximated position;

FIG. 3 is a side, perspective view of the forceps of FIG. 1;

FIG. 4 is a side, exploded perspective view of the forceps of FIG. 1shown with parts separated;

FIG. 5A is a transverse, cross-sectional view of a handle portion of theforceps of FIG. 1;

FIG. 5B is a longitudinal, cross-sectional view of the handle portion ofthe forceps of FIG. 1;

FIG. 6A is a side view of the forceps of FIG. 1 wherein a knife assemblyis disposed in a retracted position;

FIG. 6B is a side view of the forceps of FIG. 1 wherein the knifeassembly is disposed in an extended position;

FIG. 7A is a transverse, cross-sectional view of one embodiment of jawmembers configured for use with the forceps of FIG. 1;

FIG. 7B is a transverse, cross-sectional view of another embodiment ofjaw members configured for use with the forceps of FIG. 1;

FIG. 7C is a transverse, cross-sectional view of still anotherembodiment of jaw members configured for use with the forceps of FIG. 1;

FIG. 7D is a transverse, cross-sectional view of yet another embodimentof jaw members configured for use with the forceps of FIG. 1;

FIG. 8A is a side view of another embodiment of a forceps provided inaccordance with the present disclosure wherein the shaft members aredisposed in the open position;

FIG. 8B is a side view of the forceps of FIG. 8A wherein the shaftmembers are disposed in the closed position;

FIG. 9A is a side view of still another embodiment of a forceps providedin accordance with the present disclosure wherein the shaft members aredisposed in the open position; and

FIG. 9B is a side view of the forceps of FIG. 9A wherein the shaftmembers are disposed in the closed position.

DETAILED DESCRIPTION

Embodiments of the present disclosure are described in detail withreference to the drawing figures wherein like reference numeralsidentify similar or identical elements. As used herein, the term“distal” refers to the portion that is being described which is furtherfrom a user, while the term “proximal” refers to the portion that isbeing described which is closer to a user.

Turning now to FIGS. 1-4, a forceps provided in accordance with thepresent disclosure is shown generally identified by reference numeral10. Forceps 10 includes two shaft members 12 a, 12 b, each including adistal end 14 a, 14 b and a proximal end 16 a, 16 b, respectively. Eachshaft member 12 a, 12 b further includes a jaw member 120, 110 disposedat the respective distal end 14 a, 14 b thereof. Shaft members 12 a, 12b are pivotably coupled to one another about pivot 103 towards distalends 14 a, 14 b, respectively, thereof such that shaft members 12 a and12 b are moveable relative to one another from an open position (FIG.1), wherein jaw members 110 and 120 are disposed in spaced-apartrelation relative to one another, to a closed position (FIG. 2), whereinjaw members 110 and 120 are pivoted to an approximated position to grasptissue therebetween.

Each shaft member 12 a, 12 b, including respective jaw members 120, 110,is monolithically formed, e.g., as a single component. Shaft members 12a, 12 b may be formed via stamping, or via any other suitable method,e.g., casting, molding, etc. Shaft members 12 a, 12 b are formed from anelectrically conductive material, e.g., a metal, such that jaw members110, 120 each define an opposed tissue sealing surface 112, 122,respectively, that, as will be described in greater detail below, isadapted to connect to a source of electrical energy (not explicitlyshown) for sealing tissue grasped between jaw members 110, 120. Further,a longitudinally-extending knife channel 114, 124, may be defined withinone or both of jaw members 110, 120, respectively, to permitreciprocation of a knife bar 45 therethrough to cut the previouslysealed tissue.

Referring still to FIGS. 1-4, each shaft member 12 a, 12 b of forceps 10defines a handle portion 18 a, 18 b toward a proximal end 16 a, 16 b,respectively, thereof and, as mentioned above, includes respective jawmembers 120, 110 disposed at distal ends 14 a, 14 b, respectively,thereof. Further, shaft member 12 a defines a bifurcated configurationtoward a distal end 14 a thereof such that, as best shown in FIG. 3,shaft member 12 b may pass between the bifurcated portion of shaftmember 12 a adjacent pivot 103. An insulative sleeve 30 is disposedabout shaft member 12 b adjacent pivot 103 to inhibit contact betweenshaft members 12 a, 12 b as shaft member 12 b passes between shaftmember 12 a. As can be appreciated, insulative sleeve 30 maintainselectrical isolation between shaft members 12 a, 12 b.

With continued reference to FIGS. 1-4, handle portions 18 a, 18 b ofshaft members 12 a, 12 b, respectively, define substantially hollowconfigurations. More specifically, handle portions 18 a, 18 b of shaftmembers 12 a, 12 b, respectively, define opposed U-shaped configurationshaving hollow interior troughs 21 a, 21 b, respectively. As will bedescribed in greater detail below, hollow interior troughs 21 a, 21 b,respectively, of handle portions 18 a, 18 b, respectively, definerespective longitudinal tracks 22 a, 22 b configured to guide thetranslation of knife assembly 40 therethrough.

Each handle portion 18 a, 18 b further includes anelectrically-insulative coating, or covering 19 a, 19 b, respectively,disposed thereon. More specifically, handle portions 18 a, 18 b may bedip coated with an insulative material, may include a form-fittedinsulative jacket disposed thereabout, or may be otherwise configured toinclude an insulating outer layer disposed about a substantial portionthereof. As can be appreciated, electrically-insulative coverings 19 a,19 b permit the user to grasps shaft members 12 a, 12 b of forceps 10without the need for insulative gloves (not shown) or other specializedequipment.

With continued reference to FIGS. 1-4, forceps 10 further includes aknife assembly 40 operably coupled between shaft members 12 a, 12 b.Knife assembly 40 includes a handle portion 42 having a finger ring 43and a knife bar 45 extending distally from handle portion 42 to define acutting distal end 46. Handle portion 42, similar to handle portions 18a, 18 b of shaft members 12 a, 12 b, respectively, may include aninsulative coating, or covering 44 disposed thereabout, allowing theuser to grasp finger ring 43 without the need for additional protection.Alternatively, handle portion 42 of knife assembly 40 may be formed fromplastic and may be molded to the metal knife bar 45. Knife bar 45includes a longitudinally-extending slot 47 defined therein configuredto permit reciprocation of knife bar 45 relative to pivot 103. Moreparticularly, pivot 103 is disposed through slot 47 to permit knifeassembly 40 to be moved relative to jaw members 110, 120 between aretracted position (FIG. 6A) and an extended position (FIG. 6B). Variousconfigurations of knife bar 45 will be described in greater detailhereinbelow with reference to FIGS. 7A-7D.

Finger ring 43 of handle portion 42 of knife assembly 40, as shown inFIGS. 1-4, is disposed within troughs 21 a, 21 b of U-shaped hollowshaft members 12 a, 12 b, respectively, and may be configured to set agap distance “g” between jaw members 110, 120 when jaw members 110, 120are moved to the approximated position. More specifically, finger ring43 is positioned between shaft members 12 a, 12 b and defines asufficient outer diameter “d” to inhibit shaft members 12 a, 12 b frombeing moved beyond the closed position wherein tissue sealing surfaces112, 122 of respective jaw members 110, 120 are in contact with oneanother. In other words, finger ring 43 physically inhibits furtherclosure of shaft members 12 a, 12 b, e.g., since finger ring 43 isdisposed therebetween, thereby defining a minimum gap distance “g”between jaw members 110, 120 corresponding to the position wherein shaftmembers 12 a, 12 b can no longer be further closed relative to oneanother. As can be appreciated, the specific outer diameter “d” offinger ring 43 may be provided in accordance with the desired gapdistance “g” between jaw members 110, 120 when jaw members 110, 120 aredisposed in the approximated position. Further, finger ring 43 mayinclude diameter-enlarging attachments (not shown), or other featuresconfigured to increase the relative outer diameter “d” of finger ring 43to thereby increase the gap distance “g” between jaw members 110, 120for use with various compositions and sizes of tissue to be sealed. Thegap distance “g” between sealing surfaces 112, 122 of jaw members 110,120, respectively, during sealing of tissue grasped therebetween may bein the range of about 0.001 inches to about 0.006 inches.

Referring now to FIGS. 5A-5B and 6A-6B, finger ring 43 is furtherconfigured to guide knife assembly 40 as knife assembly 40 is translatedbetween the retracted position (FIG. 6A) and the extended position (FIG.6B) to cut tissue grasped between sealing surfaces 112, 122 of jawmembers 110, 120, respectively. More specifically, as mentioned above,opposed U-shaped troughs 21 a, 21 b of respective handle portions 18 a,18 b of shaft members 12 a, 12 b, respectively, are shaped to definerespective longitudinal tracks 22 a, 22 b. Longitudinal tracks 22 a, 22b guide finger ring 43, on either side thereof as finger ring 43 istranslated between the retracted position and the extended position,thereby helping to maintain a substantially straight blade path as knifebar 45 is translated through knife channels 114, 124 defined within jawmembers 110, 120, respectively. As can be appreciated, U-shaped troughs21 a, 21 b of handle portions 18 a, 18 b of shaft members 12 a, 12 b,respectively, inhibit eccentric translation of knife assembly 40 bysubstantially confining finger ring 43 to longitudinal movement alongtracks 22 a, 22 b of shaft members 12 a, 12 b, respectively. As bestshown in FIG. 5A, longitudinal tracks 22 a, 22 b and finger ring 43 ofhandle portion 42 of knife assembly 40 may define complementarytransverse, cross-sectional configurations to facilitate relativelysmooth and translation of knife assembly 40 between the retracted andextended positions.

As shown in FIGS. 2-3, and as mentioned above, shaft member 12 a and/orshaft member 12 b is adapted to connect to a source of electrical energy(not explicitly shown) for energizing sealing surfaces 112, 122 of jawmembers 110, 120, respectively, to seal tissue grasped therebetween.More particularly, wires 70, 80 are coupled to the source of energy (notexplicitly shown) at one end. Each wire 70, 80 extends through arespective proximal aperture 13 a, 13 b defined within handle portions18 a, 18 b of shaft members 12 a, 12 b, respectively. Wire 80, e.g., thenegative, or return wire 80, is coupled directly to theelectrically-conductive surface of shaft member 12 b, e.g., a portion ofshaft member 12 b that is not covered by insulative coating 30, towardproximal end 16 b thereof. Wire 70, e.g., the positive, or supply wire70, on the other hand, extends distally along shaft member 12 a andthrough a slot 17 a defined within shaft member 12 a towards distal end14 a thereof. This configuration may also be reversed, e.g., where thereturn wire 80 is coupled to shaft member 12 a and the supply wire 70 iscoupled to shaft member 12 b, or any other suitable configuration forcoupling electrical energy to shaft member 12 a and/or 12 b may beprovided. Alternatively, forceps 10 may be configured as a monopolardevice.

With continued reference to FIGS. 2-3, wire 70 is coupled to shaftmember 12 a via an actuator 90, allowing the user to selectively supplyelectrical energy to shaft members 12 a, 12 b and, thus, to sealingsurfaces 122, 112 of jaw members 120, 110, respectively, due to theelectrically conductive configuration of shaft members 12 a, 12 b. Theconstruction of shaft members 12 a, 12 b entirely from a conductivematerial also provides a larger surface area for heat dissipation duringthe tissue sealing process.

Any suitable actuator 90 for controlling the supply of electrical energyto sealing surfaces 112, 122 of members 110, 120, respectively, may beprovided.

Referring now to FIGS. 7A-7D, in conjunction with FIG. 4, variousconfigurations of the knife bar 45 of knife assembly 40 andcorresponding knife channels 114, 124, defined within jaw members 110,120, respectively, will be described. As shown in FIG. 7A, knife bar 45a defines a generally “I”-shaped configuration and blade channels 114 a,124 a correspondingly define complementary configurations to permitreciprocation of “I”-shaped knife bar 45 a therethrough. The bodyportion 48 a of “I”-shaped knife bar 45 may be formed from a metal,e.g., via stamping, while the first and second flanges 49 a of knife bar45 a may be formed from a plastic. The plastic flanges 49 a may bemolded or otherwise coupled to body portion 48 a of knife bar 45 a atthe opposed ends thereof. Alternatively, the entire knife bar 45 a maybe formed from metal.

FIG. 7B shows another configuration wherein knife bar 45 b defines alinear configuration and blade channels 114 b, 124 b each define similarconfigurations for reciprocation of knife bar 45 b therethrough.

FIG. 7C shows yet another configuration of a knife bar 45 c andcorresponding knife channels 114 c, 124 c that is similar to knife bar45 a and knife channels 114 a, 124 a of FIG. 7A, except that flanges 49c of knife bar 45 c extend in only one direction from knife body 48 c.However, flanges 49 c of knife bar 45 c may alternatively be configuredto extend in opposite directions. Knife channels 114 c, 124 c of jawmembers 110, 120, respectively, as can be appreciated, are formedcomplementarily to the configuration of knife bar 45 c. As in theembodiment of FIG. 7A, flanges 49 c may be formed from plastic, or othersuitable material, and may be molded to the metal body portion 48 c ofknife bar 45 c, or may be monolithically formed with body portion 48 cas a single component.

FIG. 7D shows still another configuration of a knife bar 45 d andcorresponding knife channel 124 d similar to knife bar 45 a and knifechannels 114 a, 124 a of FIG. 7A, except that only one of jaw members110, 120, e.g., jaw member 120, includes a knife channel 124 d definedtherein. However, this configuration may be reversed, e.g., where onlyjaw member 110 includes the knife channel defined therein. Flange 49 dof knife bar 45 d may be formed from plastic, or other suitablematerial, and knife body 48 d may be formed from metal, as discussedabove. Other configurations of the knife bar 45 and the correspondingknife channel(s) 114, 124 similar to those described about withreference to FIGS. 7A-7D may also be provided.

The use and operation of forceps 10 will now be described with referenceto FIGS. 1-2 and 6A-6B. Initially, as shown in FIG. 1, with shaftmembers 12 a, 12 b disposed in the open position and, thus, with jawmembers 110, 120 disposed in the spaced-apart position, forceps 10 ismoved into position such that tissue to be grasped, sealed and dividedis disposed between sealing surfaces 112, 122 of jaw members 110, 120,respectively. In this position, knife assembly 40 is disposed in theretracted position, wherein knife bar 45 is positioned proximally of jawmembers 110, 120, e.g., such that distal cutting edge 46 of knife bar 45does not extend between jaw members 110, 120.

Once forceps 10 is positioned as desired, the user may grasp handleportions 18 a, 18 b of shaft members 12 a, 12 b, respectively, andsqueeze shaft members 12 a, 12 b towards the closed position, as bestshown in FIG. 2, thereby pivoting jaw members 110, 120 toward theapproximated position to grasp tissue therebetween. More specifically,shaft members 12 a, 12 b are moved toward one another until shaftmembers 12 a, 12 b each contact opposed sides of finger ring 43 of knifeassembly 40, which blocks, or inhibits further closure of shaft members12 a, 12 b. This position corresponds to the closed position of shaftmembers 12 a, 12 b and, thus, the approximated position of jaw members110, 120. This closed position is regulated to assume a consistentclosure pressure between jaw members 110, 120 to effect a quality tissueseal. Typically, the closure pressure between jaw members 110, 120 is inthe range from about 3 kg/cm² to about 16 kg/cm². Further, as mentionedabove, finger ring 43 is configured such that a minimum gap distance “g”is defined between sealing surfaces 112, 122 of jaw members 110, 120,respectively, when jaw members 110, 120 are moved to the approximatedposition. The user may maintain jaw members 110, 120 in thisapproximated position grasping tissue therebetween simply by maintainingshaft members 12 a, 12 b in contact with finger ring 43 of knifeassembly 40, e.g., by retaining shaft members 12 a, 12 b in the closedposition abutting finger ring 43 of knife assembly 40. At this point,knife assembly 40 remains disposed in the retracted position (see FIG.6A).

With jaw members 110, 120 disposed in the closed position graspingtissue therebetween, electrical energy may be supplied to sealingsurfaces 112, 122 of jaw members 110, 120, respectively, to conductenergy through tissue grasped between jaw members 110, 120 to effect atissue seal. More particularly, the user may depress, or otherwiseactivate actuator 90 to supply electrical energy to shaft member 12 aand/or shaft member 12 b. Since each shaft member 12 a, 12 b, includingjaw members 120, 110 and sealing surfaces 122, 112, respectively, isformed form a conductive material, the energy supplied to shaft member12 a and/or shaft member 12 b energizes sealing surfaces 122, 112 suchthat energy is conducted therebetween and through tissue to effect atissue seal. As discussed above, the gap distance “g” between sealingsurfaces 112, 122, which is defined by finger ring 43, and regulatingthe closure pressure between jaw members 110, 120, helps ensureformation of an adequate tissue seal. Further, as mentioned above,during tissue sealing, heat is dissipated throughout shaft members 12 aand 12 b, which provide a relatively large surface area for heatdissipation, thereby reducing the overall heating of shaft members 12 a,12 b. Insulative coatings 19 a, 19 b disposed about handle portions 18a, 18 b of shaft members 12 a, 12 b help protect the user from directlycontacting the heated shaft members 12 a, 12 b.

Referring to FIGS. 8A-8B, finger ring 43 may also include one or morecontacts 52 a, 52 b that are configured to engage correspondingcontact(s) 53 a, 53 b disposed within track 22 a and/or track 22 b ofshaft members 12 a, 12 b, respectively, to close an electrical circuitupon movement of shaft members 12 a, 12 b, to the approximated position.When the electrical circuit is closed, or completed, actuator 90 isoperable to activate, or supply energy to jaw members 110, 120. Morespecifically, as shaft members 12 a, 12 b are moved to the approximatedposition about finger ring 43, electrical contacts 52 a, 52 b, of fingerring 43 are urged into contact with respective electrical contacts 53 a,53 b of shaft members 12 a, 12 b, respectively, to complete, or closethe circuit, thus allowing activation of actuator 90 to supply energy tojaw members 110, 120. In other words, electrical contacts 52 a, 52 b andcorresponding electrical contacts 53 a, 53 b permit activation ofactuator 90 only when jaw members 110, 120 are disposed in the closedposition, e.g., when contacts 52 a and 53 a and contacts 52 b and 53 bare in electrical contact with one another. Such a safety feature helpsprevent inadvertent energization of forceps 10, e.g., when jaw members110, 120 are not disposed in the closed position.

Alternatively, as opposed to point contacts 52 a, 52 b, 53 a, 53 b,shown in FIGS. 8A-8B, finger ring 43 and shaft members 12 a, 12 b mayinclude slide contacts (not explicitly shown), or any other suitableelectrical or electro-mechanical connections that inhibit activation ofactuator 90 when jaw members 110, 120 are disposed in the open position.Further, rather than completing an electrical circuit upon contact,contacts 52 a, 52 b of finger ring 43 and electrical contacts 53 a, 53 bof tracks 22 a, 22 b of shaft members 12 a, 12 b, respectively, may bepressure-sensitive contacts. In such an embodiment, activation ofactuator 90 is inhibited until a specific minimum pressure betweencontacts 52 a and 53 a and/or between contacts 52 b, 53 b is achieved,e.g., until shaft members 12 a, 12 b are moved into approximation aboutfinger ring 43 to exert a specific minimum pressure on finger ring 43.As discussed above, the relative approximation of shaft members 12 a, 12b effects both the gap distance “g” between jaw members 110, 120 and theclosure pressure between jaw members 110, 120. Thus, thepressure-sensitive contacts may be used to inhibit activation ofactuator 90 until a desired gap distance “g” and/or closure pressurebetween jaw members 110, 120 is achieved. As mentioned above, the gapdistance “g” preferably falls within a range of about 0.001 inches toabout 0.006 includes with the closure pressure in the range of about 3kg/cm² to about 16 kg/cm^(2.)

Referring now to FIGS. 6A-6B, once tissue grasped between jaw members110, 120 has been sealed, or where only tissue division is desired,knife assembly 40 may be advanced from the retracted position (FIG. 6A)to the extended position (FIG. 6B) to cut tissue grasped between jawmembers 110, 120. More particularly, when it is desired to cut tissuegrasped between jaw members 110, 120, the user may insert a fingerthrough finger ring 43 of knife assembly 40 and translate finger ring 43distally such that knife bar 45 is advanced through blade channels 114,124 of jaw members 110, 120, allowing distal cutting edge 46 to betranslated through tissue grasped between jaw members 110, 120. Asfinger ring 43 is translated distally, pivot 103 is translatedproximally through slot 47 defined within knife bar 45. Longitudinaltracks 22 a, 22 b defined within handle portions 18 a, 18 b of shaftmembers 12 a, 12 b, respectively, guide the translation of knifeassembly 40 between the retracted and extended positions. In particular,tracks 22 a, 22 b inhibit eccentric movement of knife bar 45 throughknife channels 114, 124 of jaw members 110, 120, respectively, as knifeassembly 40 is translated relative to jaw members 110, 120, therebyreducing the likelihood of blade splay and allowing for a relativelyeasy translation of distal cutting edge 46 of knife bar 45 throughtissue. Translation of knife bar 45 through knife channels 114, 124 mayalso be facilitated by the configuration of knife bar 45, e.g., theconfiguration of knife bars 45 a-45 d and corresponding knife channels114, 124, discussed above with reference to FIGS. 7A-7D.

Forceps 10 may also include a knife lock feature (not explicitly shown)configured to inhibit deployment of knife bar 45 when jaw members 110,120 are disposed in the open position and/or configured to inhibitmovement of jaw members 110, 120 to the open position when knife bar 45is disposed in the extended position. In the embodiments of FIGS. 7A and7C, discussed above, knife bars 45, 45 c are inhibited from beingdeployed, e.g., from the retracted position to the extended position,when jaw members 110, 120 are disposed in the open position due to theconfiguration of knife bars 45 a, 45 c and corresponding blade channels114 a, 124 a and 114 c, 124 c, respectively. In other words, only whenjaw members 110, 120 are in the closed position are flanges 49 a, 49 caligned with blade channels 114 a, 124 a and 114 c, 124 c, respectively,to permit translation of knife bars 45 a, 45 c, respectively,therethrough. When jaw members 110, 120 are in the open position,translation of knife bars 45 a, 45 c is inhibited. Similarly, when knifebars 45 a, 45 c are disposed in the extended position, jaw members 110,120 are inhibited from being moved to the open position due to theengagement of flanges 49 a, 49 c within respective blade channels 114 a,124 a and 114 c, 124 c. However, in these embodiments, or in any otherembodiment, shaft members 12 a, 12 b and/or jaw members 110, 120 offorceps 10 may additionally, or alternatively, include specific featuresconfigured to inhibit advancement of knife bar 45 when jaw members 110,120 are disposed in the open position. For example, commonly-owned U.S.Pat. No. 7,252,667 to Moses et al., the entire disclosure of which ishereby incorporated by reference herein, discloses a safety lockoutmechanism that prevents advancement of the cutting mechanism until thejaw members are moved to the closed position. The safety lockoutmechanism is automatically disengaged upon movement of the jaw membersto the closed position to permit advancement of the cutting mechanism,e.g., from the retracted position to the extended position.

Once tissue has been sealed and divided, finger ring 43 may betranslated proximally back to the retracted position, as shown in FIG.6A. Thereafter, shaft members 12 a, 12 b may be moved apart from oneanother to the open position such that jaw members 110, 120 are moved tothe spaced-apart position. Forceps 10 may then be removed from thesurgical site.

Referring now to FIGS. 9A-9B, another embodiment of a finger ring 143configured for use with forceps 10 is shown. Finger ring 143 is similarto finger ring 43 (see FIG. 4), discussed above, except that finger ring143 is formed from a resiliently compressible material, e.g., silicon orany other suitable polymer. Compressible finger ring 143 assures aconstant closing pressure between jaw members 110, 120 duringapproximation of shaft members 12 a, 12 b. More specifically, fingerring 143 may be configured to uniformly and consistently compress froman initial state having a first diameter “d” (FIG. 9A) to a compressedstate having a second diameter “d′” (FIG. 9B), that is smaller thandiameter “d,” upon movement of shaft members 12 a, 12 b to the closedposition to thereby regulate the closing pressure of jaw members 110,120.

With continued reference to FIGS. 9A-9B, when shaft members 12 a, 12 bare moved to the closed position compressing finger ring 143therebetween, finger ring 143 is disposed in the compressed statewherein finger ring 143 defines second diameter “d′.” In other words, inthis position, shaft members 12 a, 12 b are spaced apart by the seconddiameter “d′” and, accordingly, jaw members 110, 120 are separated bythe desired minimum gap distance “g” (see FIG. 2). Second diameter “d′”may thus be selected in accordance with the desired minimum gap distance“g” (see FIG. 2) between jaw members 110, 120, respectively, similarlyas discussed above. Further, the material(s) comprising finger ring 143may be selected to achieve a desired compressibility. More particularly,where a greater closing pressure between jaw members 110, 120 isdesired, a finger ring 143 including a relatively more-compressiblematerial may be chosen. On the other hand, where a smaller closingpressure is desired a relatively more-compressible material may bechosen. Alternatively, the material may be selected to achieve aparticular closure pressure between jaw members 110, 120 that fallswithin a desired range, e.g., from about 3 kg/cm² to about 16 kg/cm^(2.)

As discussed above, each shaft member 12 a, 12 b, including jaw members120, 110, respectively, may be formed as a single component, e.g., viastamping. The relatively inexpensive and simplistic stamping processallows for a reduced overall cost in manufacture of shaft members 12 a,12 b. Knife bar 45 may also be formed from stamping. Dip coating, orotherwise insulating handle portions 18 a, 18 b of shaft members 12 a,12 b and molding (or dip coating) handle portion 42 of knife assembly 40are also relatively simple and inexpensive processes. Further, sinceknife assembly 40 defines the gap distance “g” between jaw members 110,120, the need for providing other gap setting features is obviated. Putmore generally, forceps 10 provides a relatively inexpensive device tomanufacture, while still being capable of effectively grasping, sealing,and/or dividing tissue.

From the foregoing and with reference to the various figure drawings,those skilled in the art will appreciate that certain modifications canalso be made to the present disclosure without departing from the scopeof the same. While several embodiments of the disclosure have been shownin the drawings, it is not intended that the disclosure be limitedthereto, as it is intended that the disclosure be as broad in scope asthe art will allow and that the specification be read likewise.Therefore, the above description should not be construed as limiting,but merely as exemplifications of particular embodiments. Those skilledin the art will envision other modifications within the scope and spiritof the claims appended hereto.

What is claimed is:
 1. A forceps, comprising: first and second jawmembers; first and second handles operably coupled to the first andsecond jaw members such that at least one of the first or second handlesis moveable relative to the other between an open position and a closedposition for moving the first and second jaw members between aspaced-apart position and an approximated position, wherein the firstand second handles are monolithically formed with the respective firstand second jaw members; and a knife including a finger handle disposedbetween the first and second handles, the finger handle configured toblock further closure of the first and second handles beyond the closedposition of the first and second handles, thereby defining a minimum gapdistance between the first and second jaw members, the knifelongitudinally translatable along a longitudinal axis defined betweenthe first and second jaw members between a retracted position in whichthe knife is disposed proximal of the first and second jaw members andan extended position in which the knife is at least partially disposedwithin at least one of the first or second jaw members.
 2. The forcepsaccording to claim 1, wherein the minimum gap distance between the firstand second jaw members is in the range of 0.001 inches to 0.006 inches.3. The forceps according to claim 1, wherein at least one of the firstand second jaw members is adapted to connect to a source ofelectrosurgical energy.
 4. The forceps according to claim 1, wherein atleast one of the first or second jaw members includes alongitudinally-extending knife channel defined therein, thelongitudinally-extending knife channel configured to permitreciprocation of the knife therethrough.
 5. The forceps according toclaim 1, wherein the knife includes a slot defined therein, the slotconfigured to receive a pivot pin therethrough upon which the first andsecond jaw members are pivotably coupled, the pivot pin configured totranslate along the slot as the knife is translated between theretracted position and the extended position.
 6. A forceps, comprising:first and second jaw members; first and second handles operably coupledto the first and second jaw members such that at least one of the firstor second handles is moveable relative to the other between an openposition and a closed position for moving the first and second jawmembers between a spaced-apart position and an approximated position,the first and second handles defining respective first and secondtroughs, wherein each handle and its respective jaw member aremonolithically formed as a single component; and a knife including afinger handle, at least a portion of the finger handle disposed withineach of the first and second troughs, the first and second troughsconfigured to guide longitudinal translation of the knife in a directionalong a longitudinal axis of the forceps defined between the first andsecond jaw members between a retracted position in which the knife isproximal of the first and second jaw members and an extended position inwhich the knife is at least partially disposed within at least one ofthe first or second jaw members.
 7. The forceps according to claim 6,wherein, in the extended position, the knife extends between the firstand second jaw members.
 8. The forceps according to claim 6, wherein thefinger handle of the knife and the troughs of the first and secondhandles define complementary transverse, cross-sectional configurationsto facilitate translation of the knife between the retracted positionand the extended position.
 9. The forceps according to claim 6, whereinat least one of the first and second jaw members is adapted to connectto a source of electrosurgical energy.
 10. The forceps according toclaim 6, wherein at least one of the first and second jaw membersincludes a longitudinally-extending knife channel defined therein, thelongitudinally-extending knife channel configured to permitreciprocation of the knife therethrough.
 11. The forceps according toclaim 6, wherein the finger handle includes at least one contact that isconfigured to engage at least one corresponding contact disposed withinthe trough of at least one of the first and second handles to close anelectrical circuit upon movement of the first and second jaw members tothe approximated position.
 12. The forceps according to claim 6, whereinthe finger handle includes at least one pressure contact configured toengage at least one corresponding pressure contact disposed within thetrough of at least one of the first and second handles to close anelectrical circuit between the first and second jaw members uponexertion of a pre-determined pressure between the at least one pressurecontact of the finger handle and the at least one corresponding pressurecontact disposed within the trough of at least one of the first andsecond handles.
 13. A forceps, comprising: first and second jaw members;first and second handles operably coupled to the first and second jawmembers such that at least one of the first or second handles ismoveable relative to the other between an open position and a closedposition for moving the first and second jaw members between aspaced-apart position and an approximated position, each of the firstand second handles having a pair of sidewalls that extend in a directionalong a longitudinal axis of the forceps to define respective first andsecond troughs therebetween, each of the first and second handles havinga base that extends in a direction transverse to the longitudinal axisfrom a first sidewall of the pair of sidewalls to a second sidewall ofthe pair of sidewalls to interconnect the pair of sidewalls; and a knifeincluding a finger handle having a first diameter, the finger handledisposed between the first and second handles, at least a portion of thefinger handle disposed within each of the troughs of the first andsecond handles, the finger handle configured to contact the base of eachof the first and second troughs such that the finger handle iscompressible from the first diameter to a second diameter to define aminimum gap distance between the jaw members when the jaw members aredisposed in the approximated position, the troughs further configuredfor guiding translation of the knife between a retracted position and anextended position.
 14. The forceps according to claim 13, wherein atleast one of the first and second jaw members is adapted to connect to asource of electrosurgical energy.
 15. The forceps according to claim 13,wherein the minimum gap distance between the first and second jawmembers is in the range of about 0.001 inches to about 0.006 inches. 16.The forceps according to claim 13, wherein at least one of the first andsecond jaw members includes a longitudinally-extending knife channeldefined therein, the longitudinally-extending knife channel configuredto permit reciprocation of the knife therethrough.
 17. The forcepsaccording to claim 13, wherein the finger handle of the knife and thetroughs define complementary transverse, cross-sectional configurationsto facilitate translation of the knife between the retracted positionand the extended position.
 18. The forceps according to claim 13,wherein the troughs are configured for guiding translation of the entirefinger handle along the longitudinal axis such that the knife istranslated between the retracted position and the extended position.